1. Field of the Invention
The present invention relates to improvements in a machine for removing an old track and laying a new track, which comprises a device for receiving old ties, a first conveyor device arranged adjacent thereto for conveying the old ties away from the device for receiving the old ties, and a second conveyor device for conveying new ties to a device for laying new ties. This invention also relates to an improved method.
2. Description of the Prior Art
Such machines are well known and exemplified in EP 1 179 635 A2. The machine comprises a machine frame movable along a track, which comprises two machine frame parts linked to each other, and devices for receiving old ties and laying new ties, as well as conveyors for removing the old ties and conveyor the new ties mounted on the machine frame.
It is the primary object of this invention to improve a machine of this type by enabling old ties in good condition to be reused in the new track in a simple and cost-effective manner.
This and other objects are accomplished according to one aspect of the invention in a machine of the above-described structure with a transfer device having a vertically adjustable transfer element for selectively transferring old ties from the first to the second conveyor device, and drive means for vertically adjusting the transfer element.
According to another aspect, in a continuous method for removing an old track and laying a new track, which comprises the steps of simultaneously removing old ties in one conveying direction and conveying new ties to a tie laying device in the opposite conveying direction, the present invention provides the step of selectively deflecting old ties being removed in the one conveying direction to being conveyed in the opposite conveying direction to the tie laying device.
With this improvement in the machine and method, it is possible to reuse old ties that are still in good condition in a very economical manner. It is no longer required to convey all the old ties to freight cars and to store them on the cars, where they may be sorted in a time-consuming and labor-intensive manner, with reusable old ties being stored separately and then conveyed back to the track renewal site. Rather, these reusable old ties can now be relayed directly at the renewal site together with the new ties, at a minimal machine construction cost. The old ties which cannot be reused are conveyed away and stored, as before.